The core of the star cluster in NGC 3603 is shown in great detail in an image from the Wide Field Planetary Camera 2 (WFPC2) camera on the NASA/ESA Hubble Space Telescope. The image is a colour composite of observations in the WFPC2 filters F555W (blue), F675W (green) and F814W (red). This view shows the second of two images taken ten years apart that were used to detect the motions of individual stars within the cluster for the first time. The field of view is about 20 arcseconds across. Credit: NASA, ESA and Wolfgang Brandner (MPIA), Boyke Rochau (MPIA) and Andrea Stolte (
By exploiting the exquisite image quality of the NASA/ESA Hubble Space Telescope and comparing two observations made ten years apart astronomers have, for the first time, managed to measure the tiny motions of several hundred young stars within the central cluster of the star-forming region NGC 3603.